I can answer the vent issue. It’s a common issue, I have a 98 LeSabre which has the same control box. The vacuum is connected via a male female conector at the programer (name for the box behind the glove box). The rubber in the male conector gets soft over the years and collapse when vacuum is applied. The way to fix it for 1.60 and about 30 min of time. First you need to remive the programer and then open it up. Cut out the male plug and bring it the autoparts store. You need to buy some small vac line that will fit over the vac line that used to hook into the back of the male plug. Back at the car attach a length of vac line to the loose vac lines that were running to the back of the male plug. Push the other ends into the Oppropriate female plugs.